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A166798 Number of nX2 1..5 arrays containing at least one of each value, all equal values connected, rows considered as a single number in nondecreasing order, and columns considered as a single number in nondecreasing order. 0
0, 0, 105, 767, 3160, 9756, 25163, 57293, 118936, 229824, 419277, 729531, 1219856, 1971580, 3094143, 4732313, 7074704, 10363744, 14907249, 21091767, 29397864, 40417532, 54873907, 73643493, 97781096, 128547680 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

FORMULA

Empirical: a(n)=(n^8+32*n^7+476*n^6+3038*n^5-1141*n^4-35182*n^3+53584*n^2-25848*n+5040)/5040

EXAMPLE

Some solutions for n=4

...1.3...2.3...1.2...1.4...1.2...1.4...1.3...1.4...2.4...1.2...1.2...1.1...1.5

...4.2...4.3...4.2...1.4...3.3...2.2...2.3...3.2...3.1...3.4...2.2...1.4...2.2

...4.5...5.1...4.3...2.3...3.3...2.3...4.4...3.2...3.3...4.4...2.3...2.2...3.4

...5.5...5.1...4.5...2.5...4.5...2.5...4.5...3.5...3.5...4.5...5.4...3.5...4.4

------

...2.3...1.4...1.2...1.4...1.5...1.1...1.1...1.3...1.2...1.2...1.2...1.2...1.1

...3.3...3.2...1.4...3.4...2.2...2.3...1.2...3.3...3.3...3.2...5.3...4.3...2.3

...4.1...3.3...3.3...3.4...3.3...4.5...4.3...4.4...3.4...4.2...5.4...5.3...3.3

...4.5...5.3...3.5...5.2...4.3...4.5...4.5...5.2...5.4...5.5...5.4...5.3...5.4

CROSSREFS

Sequence in context: A152826 A133767 A166816 * A033593 A058844 A165382

Adjacent sequences:  A166795 A166796 A166797 * A166799 A166800 A166801

KEYWORD

nonn

AUTHOR

R. H. Hardin (rhhardin(AT)att.net) Oct 21 2009

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Last modified February 17 00:09 EST 2012. Contains 205978 sequences.